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高维多重双正交小波包 被引量:21
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作者 陈清江 程正兴 冯晓霞 《应用数学》 CSCD 北大核心 2005年第3期358-364,共7页
本文给出对应于高维多重尺度函数的双正交多小波包的定义及其构造方法.讨论了高维不可分双正交多小波包的双正交性.
关键词 矩阵序列 矩阵符号 加细方程 多重多分辨分析 双正交 多重尺度函数 多重小波包
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基于双正交法的焊缝早期隐性损伤临界状态磁记忆特征 被引量:18
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作者 邢海燕 王犇 +2 位作者 王学增 刘长海 党永斌 《机械工程学报》 EI CAS CSCD 北大核心 2015年第16期71-76,共6页
针对焊缝早期隐性损伤临界状态磁记忆特征提取及评价难题,在大量试验基础上提出双正交法:即焊缝检测路径的正交性和磁场矢量分析的正交性。以Q235B焊接试件为试验材料,通过测量焊缝纵向和横向磁记忆信号分布,引入磁场正交矢量空间图和... 针对焊缝早期隐性损伤临界状态磁记忆特征提取及评价难题,在大量试验基础上提出双正交法:即焊缝检测路径的正交性和磁场矢量分析的正交性。以Q235B焊接试件为试验材料,通过测量焊缝纵向和横向磁记忆信号分布,引入磁场正交矢量空间图和李萨如图,研究疲劳载荷下焊缝隐性损伤演化的磁记忆表征规律,对比扫描电镜和X射线检测结果,获得焊缝早期隐性损伤临界状态磁记忆特征:隐性损伤出现时李萨如图会产生涡动性的局部闭合,随着损伤的扩展涡动性局部闭合的面积越来越大直至断裂时完全闭合。在此基础上提出正交矢量梯度积分S(K)和正交矢量合成梯度比Kr的概念,建立Kr与剩余寿命Nr定量关系模型,为焊缝早期隐性损伤临界状态的定量研究提供一种新的思路。 展开更多
关键词 双正交 隐性损伤 磁记忆 焊缝
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一类多重向量值双正交小波包的刻划 被引量:7
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作者 陈清江 张同琦 +1 位作者 程正兴 李学志 《云南大学学报(自然科学版)》 CAS CSCD 北大核心 2006年第6期472-477,482,共7页
研究向量值小波包.给出一类3尺度多重向量值双正交小波包的定义及构造.运用积分理论与算子理论,刻划了多重向量值双正交小波包的特征,得到多重向量值小波包的双正交公式.进而,得到向量值函数空间L2R,Cs×s)新的Riesz基.
关键词 双正交 多重 向量值多分辨分析 向量值尺度函数 向量值小波 向量值小波包
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Biorthogonal multiple wavelets generated by vector refinement equation 被引量:5
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作者 Song LI~(1+) Jun XIAN~2 1 Department of Mathematics,Zhejiang University,Hangzhou 310027,China 2 Department of Mathematics,Sun Yat-Sen University,Guangzhou 510275,China 《Science China Mathematics》 SCIE 2007年第7期1015-1025,共11页
Biorthogonal multiple wavelets are generated from refinable function vectors by using the multiresolution analysis. In this paper we provide a general method for the construction of compactly supported biorthogonal mu... Biorthogonal multiple wavelets are generated from refinable function vectors by using the multiresolution analysis. In this paper we provide a general method for the construction of compactly supported biorthogonal multiple wavelets by refinable function vectors which are the solutions of vector refinement equations of the form $$\varphi (x) = \sum\limits_{\alpha \in \mathbb{Z}^s } {a(\alpha )\varphi (Mx - \alpha ), x \in \mathbb{R}^s } ,$$ where the vector of functions ? = (? 1, …, ? r)T is in $(L_2 (\mathbb{R}^s ))^r ,a = :(a(\alpha ))_{\alpha \in \mathbb{Z}^s } $ is a finitely supported sequence of r × r matrices called the refinement mask, and M is an s × s integer matrix such that lim n→∞ M ?n = 0. Our characterizations are in the general setting and the main results of this paper are the real extensions of some known results. 展开更多
关键词 refinement equation biorthogonal multiple wavelets refinable function vector 42C40 41A10 41A15 41A25
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A quantitative analysis method for GPR signals based on optimal biorthogonal wavelet 被引量:6
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作者 LIU Hao-ran LING Tong-hua +2 位作者 LI Di-yuan HUANG Fu ZHANG Liang 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第4期879-891,共13页
Due to the disturbances arising from the coherence of reflected waves and from echo noise,problems such as limitations,instability and poor accuracy exist with the current quantitative analysis methods.According to th... Due to the disturbances arising from the coherence of reflected waves and from echo noise,problems such as limitations,instability and poor accuracy exist with the current quantitative analysis methods.According to the intrinsic features of GPR signals and wavelet time–frequency analysis,an optimal wavelet basis named GPR3.3 wavelet is constructed via an improved biorthogonal wavelet construction method to quantitatively analyse the GPR signal.A new quantitative analysis method based on the biorthogonal wavelet(the QAGBW method)is proposed and applied in the analysis of analogue and measured signals.The results show that compared with the Bayesian frequency-domain blind deconvolution and with existing wavelet bases,the QAGBW method based on optimal wavelet can limit the disturbance from factors such as the coherence of reflected waves and echo noise,improve the quantitative analytical precision of the GPR signal,and match the minimum thickness for quantitative analysis with the vertical resolution of GPR detection. 展开更多
关键词 GPR detection signal quantitative analysis wavelet time–frequency analysis biorthogonal wavelet basis
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Representation of three-dimensional mass distribution of the Earth's interior by biorthogonal series and its use for studying internal structure of the planet
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作者 Mykhailo Fys Mariana Yurkiv +1 位作者 Andrii Brydun Andrii Sohor 《Geodesy and Geodynamics》 EI CSCD 2024年第3期264-275,共12页
This paper utilizes the mathematical concept of approximation within an ellipsoid from a single viewpoint to present the spatial mass distribution function of the Earth's interior and its internal potential.The pr... This paper utilizes the mathematical concept of approximation within an ellipsoid from a single viewpoint to present the spatial mass distribution function of the Earth's interior and its internal potential.The primary focus lies in constructing the volume distribution of masses in the planet's interior, with the expansion coefficients being linear combinations of the Stokes constants. Several possible approaches are suggested for determining accurately these coefficients employing three-dimensional(biorthogonal)polynomials. By expressing the mass distribution function of the Earth's interior and its internal potential as a series, an algorithm is introduced for the calculation of gravitational energy. It allows us to estimate fluctuations in gravitational energy. The implementation of this algorithm offers the means of establishing the extent to which the Earth deviates from a state of hydrostatic equilibrium as a celestial body.Due to the aforementioned method, calculations have been conducted to validate its effectiveness and reliability. This example is given as an illustration of a given method for studying the internal structure of planets. 展开更多
关键词 Mass distribution function Potential Stokes constants biorthogonal polynomials
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Riesz multiwavelet bases generated by vector refinement equation 被引量:3
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作者 LI Song LIU ZhiSong 《Science China Mathematics》 SCIE 2009年第3期468-480,共13页
In this paper, we investigate compactly supported Riesz multiwavelet sequences and Riesz multiwavelet bases for L 2(? s ). Suppose ψ = (ψ1,..., ψ r ) T and $ \tilde \psi = (\tilde \psi ^1 ,...,\tilde \psi ^r )^T $ ... In this paper, we investigate compactly supported Riesz multiwavelet sequences and Riesz multiwavelet bases for L 2(? s ). Suppose ψ = (ψ1,..., ψ r ) T and $ \tilde \psi = (\tilde \psi ^1 ,...,\tilde \psi ^r )^T $ are two compactly supported vectors of functions in the Sobolev space (H μ(? s )) r for some μ > 0. We provide a characterization for the sequences {ψ jk l : l = 1,...,r, j ε ?, k ε ? s } and $ \tilde \psi _{jk}^\ell :\ell = 1,...,r,j \in \mathbb{Z},k \in \mathbb{Z}^s $ to form two Riesz sequences for L 2(? s ), where ψ jk l = m j/2ψ l (M j ·?k) and $ \tilde \psi _{jk}^\ell = m^{{j \mathord{\left/ {\vphantom {j 2}} \right. \kern-0em} 2}} \tilde \psi ^\ell (M^j \cdot - k) $ , M is an s × s integer matrix such that lim n→∞ M ?n = 0 and m = |detM|. Furthermore, let ? = (?1,...,? r ) T and $ \tilde \phi = (\tilde \phi ^1 ,...,\tilde \phi ^r )^T $ be a pair of compactly supported biorthogonal refinable vectors of functions associated with the refinement masks a, $ \tilde a $ and M, where a and $ \tilde a $ are finitely supported sequences of r × r matrices. We obtain a general principle for characterizing vectors of functions ψν = (ψν1,...,ψνr ) T and $ \tilde \psi ^\nu = (\tilde \psi ^{\nu 1} ,...,\tilde \psi ^{\nu r} )^T $ , ν = 1,..., m ? 1 such that two sequences {ψ jk νl : ν = 1,..., m ? 1, l = 1,...,r, j ε ?, k ε ? s } and { $ \tilde \psi _{jk}^\nu $ : ν=1,...,m?1,?=1,...,r, j ∈ ?, k ∈ ? s } form two Riesz multiwavelet bases for L 2(? s ). The bracket product [f, g] of two vectors of functions f, g in (L 2(? s )) r is an indispensable tool for our characterization. 展开更多
关键词 vector refinement equations Riesz multiwavelet base biorthogonal wavelets 42C40 39B12 46B15 47A10 47B37
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The separable Hamiltonian system and complete biorthogonal expansion method of Mindlin plate bending problems 被引量:5
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作者 HOU GuoLin QI GaoWa +1 位作者 XU YaNan CHEN Alatancang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第5期974-980,共7页
A separable Hamiltonian system of Mindlin plate bending problems is obtained. Using the equivalence between the differen form and integral form of the separable Hamiltonian system, the biorthogonal relationships of th... A separable Hamiltonian system of Mindlin plate bending problems is obtained. Using the equivalence between the differen form and integral form of the separable Hamiltonian system, the biorthogonal relationships of the eigenfunctions are presen! Based on the biorthogonal relationships, a novel complete biorthogonal expansion of the Mindlin plate bending problems x~ two opposite sides simply supported is proposed through the products of operator matrices. The exact solutions to deflections bending moments for the Mindlin plate with fully simply supported sides are obtained. A numerical example is illustrated to ve~ the accuracy and validity of the expansion method. 展开更多
关键词 separable Hamiltonian system mindlin plate bending biorthogonal expansion off-diagonal Hamiltonian operator
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具有整数伸缩因子的多变量向量值双正交多小波包 被引量:5
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作者 朱玉清 卫艳荣 程正兴 《郑州大学学报(理学版)》 CAS 北大核心 2012年第3期61-65,共5页
研究多变量向量值双正交多小波包的构造与性质.引进了向量值多分辨分析与多变量值双正交多重小波的概念.给出多变量多重向量值双正交小波包的定义及其迭代方法.运用积分变换与有限群理论,讨论了多变量多重向量值双正交小波包的性质,得... 研究多变量向量值双正交多小波包的构造与性质.引进了向量值多分辨分析与多变量值双正交多重小波的概念.给出多变量多重向量值双正交小波包的定义及其迭代方法.运用积分变换与有限群理论,讨论了多变量多重向量值双正交小波包的性质,得到了多变量多重向量值双正交小波包的双正交公式,进而给出多变量向量值函数空间L2(Rs,Cn)的一个新的基底. 展开更多
关键词 多变量 多重 双正交 向量值多分辨分析 迭代算法 向量值小波包
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基于快速对称小波变换的高效模糊指纹图象压缩方法 被引量:3
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作者 倪林 张长水 +1 位作者 荣钢 边肇祺 《软件学报》 EI CSCD 北大核心 1996年第5期272-279,共8页
自动指纹识别系统AFIS(automatedfingerprentidentificationsystem)要求对支持该系统的数据库中的指纹图象数据进行压缩,以提高系统实用性,其恢复图象要求有很高的保真度,以避免丢失... 自动指纹识别系统AFIS(automatedfingerprentidentificationsystem)要求对支持该系统的数据库中的指纹图象数据进行压缩,以提高系统实用性,其恢复图象要求有很高的保真度,以避免丢失细节.同时,在实用系统中,还需要有较快的图象恢复时间.本文总结一种基于对称小波变换的高效模糊指纹图象压缩方法,通过对称快速小波变换,选择适当的分解方式,采用自适应标量量化,加上改进的摘编码,实现高速、高保真的要求.同时,设计一种码率控制策略,有效地控制压缩量.实验结果表明:本文的压缩方法能表现出很好的性能. 展开更多
关键词 小波变换 熵编码 图象压缩 AFIS 指纹图象
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基于小波变换的图像压缩中小波基的评价与选取 被引量:4
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作者 甘宸伊 姚远 +2 位作者 杨彦伟 刘小兵 高喆荣 《兵器装备工程学报》 CAS 2016年第12期105-107,149,共4页
针对图像压缩中小波基的选取自由度高的问题,讨论了小波基的选择依据,分析了正交性、对称性、正则性、支撑性和消失矩等性能指标对图像编码的影响。研究了利用均方误差和峰值信噪比对图像品质的评价方法。利用MATLAB仿真,采用SPIHT压缩... 针对图像压缩中小波基的选取自由度高的问题,讨论了小波基的选择依据,分析了正交性、对称性、正则性、支撑性和消失矩等性能指标对图像编码的影响。研究了利用均方误差和峰值信噪比对图像品质的评价方法。利用MATLAB仿真,采用SPIHT压缩算法,使用4种小波基对测试图像进行压缩,对比其均方误差、最大误差、峰值信噪比和压缩比,并对实验结果进行了分析,发现具有对称性和紧支撑性,正则性较好的双正交小波综合性能最好,为小波基的选择提供了参考标准。 展开更多
关键词 图像压缩 小波基 双正交 对称性 均方误差 信噪比
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General Solutions of Matrix Extension Associated with Multiple Channel Biorthogonal Wavelet Filters 被引量:1
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作者 Wen Bin WEI Min HUANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2007年第7期1241-1250,共10页
This paper is concerned with seeking the general solutions of matrix equation M(ξ)M* (ξ) = Is for the construction of multiple channel biorthogonal wavelets, provided that some special solution of its is known.
关键词 matrix extension refinement equation biorthogonal wavelet
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A General Algorithm for Biorthogonal Functions and Performance Analysis of Biorthogonal Scramble Modulation System
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作者 Yueyun Chen Zhenhui Tan 《Wireless Sensor Network》 2010年第3期199-205,共7页
Applying the theorems of Mobius inverse and Dirichlet inverse, a general algorithm to obtain biorthogonal functions based on generalized Fourier series analysis is introduced. In the algorithm, the orthogonal function... Applying the theorems of Mobius inverse and Dirichlet inverse, a general algorithm to obtain biorthogonal functions based on generalized Fourier series analysis is introduced. In the algorithm, the orthogonal function can be not only Fourier or Legendre series, but also can be any one of all orthogonal function systems. These kinds of biorthogonal function sets are used as scramble signals to construct biorthogonal scramble modulation (BOSM) wireless transmission systems. In a BOSM system, the transmitted signal has significant security performance. Several different BOSM and orthogonal systems are compared on aspects of BER performance and spectrum efficiency, simulation results show that the BOSM systems based on Chebyshev polynomial and Legendre polynomial are better than BOSM system based on Fourier series, also better than orthogonal MCM and OFDM systems. 展开更多
关键词 biorthogonal FUNCTIONS biorthogonal SCRAMBLE Modulation Generalized FOURIER Series MOBIUS INVERSE Wireless Transmission
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Seismic data compression based on integer wavelet transform 被引量:1
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作者 WANG Xi-zhen(王喜珍) TENG Yun-tian(滕云田) +1 位作者 GAO Meng-tan(高孟潭) JIANG Hui(姜慧) 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第z1期123-128,共6页
Due to the particularity of the seismic data, they must be treated by lossless compression algorithm in some cases. In the paper, based on the integer wavelet transform, the lossless compression algorithm is studied.... Due to the particularity of the seismic data, they must be treated by lossless compression algorithm in some cases. In the paper, based on the integer wavelet transform, the lossless compression algorithm is studied. Comparing with the traditional algorithm, it can better improve the compression rate. CDF (2, n) biorthogonal wavelet family can lead to better compression ratio than other CDF family, SWE and CRF, which is owe to its capability in can- celing data redundancies and focusing data characteristics. CDF (2, n) family is suitable as the wavelet function of the lossless compression seismic data. 展开更多
关键词 lossless compression integer wavelet transform lifting scheme biorthogonal wavelet
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APPLICATION OF CDF(2,2) TO ANALYSIS OF SUSPENDED SEDIMENT IMAGE 被引量:1
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作者 Hequan Sun Liansheng Yu +2 位作者 Yongming Shen Daoyin Yu Guangwen Zhu 《China Particuology》 SCIE EI CAS CSCD 2005年第4期204-207,共4页
The characteristics of suspended sediment image can be reflected by the coefficients of biorthogonal wavelet transform of CDF(2,2). Based on the power distribution in different scales, an adaptive algorithm is propo... The characteristics of suspended sediment image can be reflected by the coefficients of biorthogonal wavelet transform of CDF(2,2). Based on the power distribution in different scales, an adaptive algorithm is proposed in this paper, whereby the coefficients are adjusted non-linearly. The particle information can be well retained while the useless background is removed. In this way, satisfactory binary image can be obtained for further analysis of the sediment particle. 展开更多
关键词 suspended sediment image PARTICLE biorthogonal wavelet CDF(2 2)
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多元双正交小波包的构造及性质 被引量:3
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作者 陈清江 冯金顺 程正兴 《南昌大学学报(理科版)》 CAS 北大核心 2007年第1期13-17,共5页
给出具任意整数矩阵伸缩的多元不可分双正交小波包的定义及其构造算法。运用代数学理论,积分变换与算子理论,讨论了多元不可分双正交小波包的性质。得到L2(Rn)的小波包基的直和分解。
关键词 加细方程 多分辨分析 双正交 尺度函数 小波包
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α尺度的二维四向小波问题 被引量:3
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作者 库福立 王刚 库媛 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2013年第5期763-782,共20页
以双向小波理论为基础,通过使用张量积的方法构造尺度为α的二维四向小波,并给出了二维小波的多分辨分析及二维小波的正交条件和双正交条件,得到了二维四向小波包及其相关性质.
关键词 二维四向小波 双正交 多分辨分析 两尺度方程 加细面具
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一种双正交零中频接收机的设计和电路实现 被引量:3
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作者 田克纯 周武中 +1 位作者 陈宏滨 覃远年 《西南师范大学学报(自然科学版)》 CAS CSCD 北大核心 2010年第2期142-147,共6页
零中频接收机以其低功耗和易于单片集成等优点,已经成为射频接收机发展的重要方向,但它也存在固有的缺陷,如相位偏移导致的IQ不平衡和直流漂移.双正交零中频接收机采用交叉混频的双正交结构降低IQ不平衡对相位偏移的敏感度,并采用差分... 零中频接收机以其低功耗和易于单片集成等优点,已经成为射频接收机发展的重要方向,但它也存在固有的缺陷,如相位偏移导致的IQ不平衡和直流漂移.双正交零中频接收机采用交叉混频的双正交结构降低IQ不平衡对相位偏移的敏感度,并采用差分放大的形式消除直流漂移问题.通过对一种双正交零中频接收机进行改进、仿真和电路实现,电路测试结果和仿真结果相符. 展开更多
关键词 零中频接收机 IQ不平衡 直流漂移 双正交
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数量矩阵伸缩的高维矩阵值小波包 被引量:3
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作者 李华 李杰 +1 位作者 江晓武 方勤华 《江西师范大学学报(自然科学版)》 CAS 北大核心 2007年第4期370-374,共5页
研究高维矩阵值双正交小波包的构造及性质.引进了基于数量矩阵伸缩的紧支撑高维矩阵值正交小波包的概念.运用傅立叶变换、积分变换和算子理论,讨论了它们的性质,得到关于高维矩阵值小波包的双正交公式.
关键词 双正交 高维 矩阵值多分辨分析 矩阵值尺度函数 矩阵值小波包
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Biorthogonal quantum criticality in non-Hermitian many-body systems 被引量:2
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作者 Gaoyong Sun Jia-Chen Tang Su-Peng Kou 《Frontiers of physics》 SCIE CSCD 2022年第3期53-61,共9页
We develop the perturbation theory of the fidelity susceptibility in biorthogonal bases for arbitrary interacting non-Hermitian many-body systems with real eigenvalues. The quantum criticality in the non-Hermitian tra... We develop the perturbation theory of the fidelity susceptibility in biorthogonal bases for arbitrary interacting non-Hermitian many-body systems with real eigenvalues. The quantum criticality in the non-Hermitian transverse field Ising chain is investigated by the second derivative of the ground-state energy and the ground-state fidelity susceptibility. We show that the system undergoes a second-order phase transition with the Ising universal class by numerically computing the critical points and the critical exponents from the finite-size scaling theory. Interestingly, our results indicate that the biorthogonal quantum phase transitions are described by the biorthogonal fidelity susceptibility instead of the conventional fidelity susceptibility. 展开更多
关键词 biorthogonal quantum criticality non-Hermitian systems fidelity susceptibility
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